Black hole scattering experiments

We perform scattering experiments of initially spinning black holes in hyperbolic encounters using numerical relativity simulations with the Einstein Toolkit/Canuda. We identify the critical impact parameter for scattering versus non-scattering binary black holes. In the case of the black holes scattering off each other, we find that the outgoing black holes are spun-up. We will discuss observational implications for gravitational wave detections, population models and for estimates of the spin distribution in black hole binaries.